JPH08126663A - Absorptive article - Google Patents

Abstract

PURPOSE: To obtain stretchability in the girth direction and good fittability to a body by preparing a back face sheet with a poreless moisture-permeable film formed of a block copolymer of a polyester resin composed of a hard component and a soft component and bonding a stretchable non-woven fabric on the moisture-permeable film. CONSTITUTION: A back face sheet 2 is prepd. with a poreless moisture-permeable film formed of a block copolymer of a polyester resin composed of a hard component and a soft component and a stretchable non-woven fabric 6 is bonded on the poreless moisture-permeable film. The non-woven fabric 6 is made into a wave-shape by providing alternately projected ridges 6' and recessed channels 6'' extending in the longitudinal direction of an absorptive body 4 to form a wall to be extensible. Then, this non-woven fabric 6 is bonded intermittently with the back face sheet 2 on outer face top ends of its recessed channels 6'' through a hot-melt adhesive 7 to make the back face sheet 2 with the non-woven fabric 6 monolithically stretchable and contractable in the width direction of the absorptive body 4. It is possible thereby to realize stretchability in the girth direction and good fittability to a body.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to absorbent articles, and more particularly to absorbent articles such as open-type diapers, pants, or brief-type diapers (including incontinence) and so-called training.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
BACKGROUND ART As absorbent articles such as pants or brief type disposable diapers, especially training pants, those in which elastic members are attached around the waist and legs and an absorbent body is interposed between a top sheet and a back sheet are known. .
In these absorbent articles, the top sheet and the back sheet do not have stretchability, or even if they have stretchability, they are not excellent. By providing a large number of gathers around the legs, workability of attachment / detachment to the body and fit to the body are obtained.

However, the absorbent article having the above structure,
Especially, the diaper has the following problems. Since the structure of the diaper becomes complicated, the number of manufacturing steps increases, resulting in poor production efficiency and high cost. Since the gathers are relatively large, the diaper becomes bulky and difficult to store and store in a compact mold. The use of the elastic member may be biased, and local pressure is applied to the body, leaving marks on the skin. The back sheet or the front sheet may cause tight spots, which may reduce the fit of the diaper. The reduced fit of the diaper may cause leakage of excrement. It is difficult to give accurate gathers, and the diaper may shift from the wearer.

Therefore, in order to solve the above-mentioned problems (1) to (3), a diaper having a structure using elastic members as the top sheet and the back sheet has been conventionally proposed. For example, JP-A-3-80859 and JP-A-3-2245.
59 and Japanese Patent Application Laid-Open No. 4-227260 describe a diaper in which a stretchable non-woven fabric is used as a surface material and a stretchable film is used as a back surface material, and both are joined.

Further, Japanese Patent Laid-Open No. 4-89050 discloses that
A diaper using an elastic elastic film as the back sheet and an elastic elastic nonwoven fabric as the surface sheet, or
A disposable diaper that is a composite sheet of a stretchable elastic film and a non-stretchable film is used as the back sheet, and a stretchable elastic nonwoven fabric and a non-stretchable nonwoven fabric are used as the top sheet. Has been described. However, although all of the above problems are solved in any of the above-described configurations, not all of them have been solved.

For example, in all of the diapers having the configurations described in the above publications, since the stretchable elastic nonwoven fabric is used for the surface sheet, various physical properties of the nonwoven fabric used as the surface sheet may be limited. .

That is, the topsheet is a member which comes into direct contact with the wearer of the diaper, and the non-woven fabric used as the topsheet is soft to the touch, irritating to the skin, liquid-permeable, liquid-diffusible, and has a covering effect on the absorber. Although it is required to control many physical properties such as prevention of liquid return, it is difficult for the diaper having the configuration described in each of the above publications to satisfy all these physical properties.

When the stretchable elastic nonwoven fabric is stretched, the basis weight, the thickness, the thickness of the fibers, the opening between the fibers, or the interfiber between the fibers when the stretched elastic nonwoven fabric is stretched is increased. Physical properties such as distance may change, and the physical properties of the surface sheet of the diaper controlled by these physical properties may not be maintained. Further, since the entire diaper is stretchable, it fits well on the body, but in the case of a back sheet having no moisture permeability, there is a risk of causing stuffiness.

As a sheet having moisture permeability and waterproofness, an olefin resin such as polyethylene or polypropylene is melt-kneaded with 40 parts by weight or more of an inorganic filler to form a sheet, and then the sheet is uniaxially or biaxially oriented. A microporous sheet obtained by stretching is known. Also,
As the above-mentioned microporous sheet, in JP-B-5-38011, a specific crystalline polymer (polypropylene or the like) and a specific compound (mineral oil or the like) are melt-kneaded, and phase separation is performed in a sheet forming (cooling) process. Although a microporous sheet obtained by stretching a sheet obtained by subjecting the sheet to the above is also proposed, the present situation is that the above-mentioned problem cannot be solved even with the microporous sheet.

Further, Japanese Patent Laid-Open No. 6-134000 proposes a non-porous stretchable moisture-permeable sheet which is obtained by laminating a specific polyurethane sheet and a stretchable nonwoven fabric.

However, the above-mentioned polyurethane sheet causes various problems as described below depending on the isocyanate used. That is, when an aromatic isocyanate is used as the above-mentioned isocyanate, since it has high reactivity with a polyol or the like which reacts with the isocyanate to form polyurethane,
Although the residual amount of unreacted isocyanate in the polyurethane sheet is small, the residual amount of unreacted isocyanate is small because the polyurethane sheet violently yellows even when stored under natural conditions, but even when stored under natural conditions, especially when exposed to light,
Since it is susceptible to discoloration and deterioration due to heat, nitric oxide gas, city combustion gas, etc., there is a problem that it yellows violently and the commercial value is significantly impaired when it is used, for example, in absorbent articles.

Further, when a non-aromatic isocyanate is used as the above-mentioned isocyanate, the obtained polyurethane sheet is hard to yellow, but the reactivity of the non-aromatic isocyanate is poor, so that unreacted isocyanate remains and, for example, absorbability. When used in articles and the like, there is a problem that the unreacted isocyanate severely irritates the skin.

Further, in the case of using both aromatic isocyanate and non-aromatic isocyanate, these isocyanates also react with moisture in the air to form a urea bond, but they react with water in the latter stage of the polymerization reaction. The reaction (1) does not reach urea bond and remains as an amine, so that there is a problem that the amine vigorously irritates the skin and causes fogging. Further, when the polyurethane sheet is decomposed, it produces an amine and becomes a base of skin irritation when used in absorbent articles and the like (especially, the above-mentioned polyurethane sheet exhibiting moisture permeability in the absence of pores is used in absorbent articles). It is more likely to be decomposed than ordinary polyurethane due to water absorption.). Further, the amine catalyst used in the urethanization reaction also becomes a skin irritation group.

In short, the above-mentioned polyurethane sheet is not preferable for applications such as absorbent articles that come into direct contact with the human body.

Therefore, an object of the present invention is to make use of the advantages of the non-woven fabric generally used in disposable diapers and to fully utilize the advantages of using a film having moisture permeability and stretchability as the back sheet. To provide.

[0016]

The present invention comprises a liquid-impermeable backsheet, a liquid-permeable topsheet, and a vertically elongated absorber disposed between the backsheet and the topsheet. In the absorbent article provided with, the back sheet is a non-porous moisture-permeable film formed of a block-copolymerized polyester resin of a hard component and a soft component, and an extensible nonwoven fabric is bonded onto the moisture-permeable film. The above object is achieved by providing an absorbent article (hereinafter, referred to as the "first invention" when referred to as the present invention).

The present invention also provides an absorbent article comprising a liquid-impermeable backsheet, a liquid-permeable topsheet, and a longitudinally elongated absorber disposed between the backsheet and the topsheet. In the above, the back sheet is a non-porous moisture permeable film formed of a block-copolymerized polyester resin of a hard component and a soft component, and the top sheet is a nonwoven fabric having a large number of stretchable folds. The absorbent article, wherein the back sheet and the top sheet are extended in the width direction of the absorbent body to form extended portions, and are joined intermittently at the extended portions. (Less than,
When the term "second invention" is used, the above object is achieved by providing this invention.

In the absorbent article of the present invention, the back sheet is made of a non-porous moisture permeable film made of a block-copolymerized polyester resin comprising a hard component and a soft component, and is intermittently provided on the non-porous moisture permeable film. The joined non-woven fabric is also formed to be stretchable, and since the back sheet and the non-woven fabric are integrally stretchable, when the user wears the back sheet and the non-woven fabric, the non-woven fabric expands and contracts in the girth direction to the body. Has a good fit and the back sheet has moisture permeability,
Does not cause stuffiness problems.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the absorbent article of the present invention will be described in more detail with reference to Examples.

Embodiment 1 (Embodiment of the First Invention) FIG. 1 is a perspective view showing a pants-type disposable diaper showing Embodiment 1 of the present invention (first invention), FIG. 2 is a development view thereof, and FIG. FIG. 3 is a sectional view taken along line I-I in FIG. 2.

The absorbent article (pants-type disposable diaper) 1 of this embodiment has a liquid-impermeable backsheet 2, a liquid-permeable topsheet 3, and the backsheet 2 as shown in FIGS. And a vertically long absorber 4 disposed between the surface sheets 3
And both sides 5a and 5a of the front part (ventral side).
And a pair of rear side (back side) side portions 5b and 5b, respectively, and is formed in a pants type having a waist opening 12 and a pair of leg openings 13 and 13, as shown in FIG. Such a structure is similar to that of a known pants-type disposable diaper.

In the pants-type disposable diaper 1 of this embodiment, as shown in FIGS. 2 and 3, the back sheet 2 is a non-porous transparent member made of a block copolymerized polyester resin composed of a hard component and a soft component. A stretchable nonwoven fabric 6 is bonded to the non-porous moisture permeable film which is a wet film.

To further explain this embodiment in detail, in the nonwoven fabric 6, as shown in FIG. 3, the ridge portions 6'and the ridge portions 6 "extending in the longitudinal direction of the absorbent body 4 are alternately connected. The ridge has a corrugated cross section, and a fold is formed by the ridge 6'and the ridge 6 ", and the fold is extendable in the width direction of the absorbent body 4. The non-woven fabric 6 is intermittently joined to the back sheet 2 via a hot melt adhesive 7 at the top of the outer surface of the recessed portion 6 ″, and the back sheet 2 is integrated with the non-woven fabric 6. The absorbent body 4 can be expanded and contracted in the width direction of the absorbent body 4. The interval between the folds in the nonwoven fabric 6, that is, the interval L between the ridges 6'and 6'is 0.5 to 1.5 mm. Yes.

The "range" in which the non-woven fabric 6 having a large number of folds can be stretched depends on the moisture permeable film forming the back sheet 2 used, but the width of the non-stretched non-woven fabric 6 (of the absorbent body 4). Ratio of width direction) to width of nonwoven fabric 6 stretched to a non-stretchable state (latter / former) [(latter;
(Stretching) / (former; non-stretching)] is particularly preferably in the range of 1.2 to 3.0.

The absorber 4 is made up of the topsheet 3
Is surrounded by both sides of the bottom surface of the absorber 4,
On the upper surface side of the absorber 4, the hot melt adhesive 7
Is joined to the surface sheet 3 by. In addition, the topsheet 3 is provided on both sides of the bottom surface of the absorber 4,
The ridge 6'of the non-woven fabric 6 by the hot melt adhesive 7
Is joined to the top end of the non-woven fabric 6 so as not to hinder the expansion of the nonwoven fabric 6.

As the constituent fibers forming the nonwoven fabric 6, the following fibers are preferred. Polyolefin-based fibers such as polyethylene or polypropylene, polyester-based, amide-based or acrylic-based synthetic fibers, regenerated fibers such as rayon or cupra, and natural fibers such as cotton, linen or silk. As a method for processing the above fibers into a non-woven fabric, an ordinary processing method can be used, and examples thereof include a heat roll bond, an air through heat bond, a spun bond, a needle punch, a spun lace or a melt blown method. be able to.

Further, the non-woven fabric 6 cannot be used as a material that hinders the demand because the touch is an important factor, but a non-woven fabric having stretch elasticity obtained from a fiber made of a stretchable elastic material. Can also be used. Examples of the elastic material include styrene rubber, olefin rubber, urethane rubber, ester rubber, amide rubber, butyl rubber graft polyethylene, 1,2-polybutadiene, and trans 1,4-polyisoprene thermoplastic elastomer. Examples thereof include those obtained by spinning one kind or a blend of two or more kinds.

The nonwoven fabric 6 has a basis weight of 10 to 10.
It is preferably 40 g / m ² . The basis weight is 10g
If it is less than / m ^2, it is difficult to obtain a uniform non-woven fabric, and the physical properties as a surface sheet may vary, and if it exceeds 40 g / m ² , the diaper becomes bulky and it becomes difficult to store and store it in a compact mold. Therefore, it is not preferable.

Examples of the surface sheet 3 include polyolefin fibers such as polyethylene or polypropylene, polyester fibers, synthetic fibers such as amide or acrylic fibers, regenerated fibers such as rayon or cupra, and natural fibers such as cotton, hemp or silk. Can be used. As the absorbent body 4, it is preferable to use a high-molecular water-absorbing polymer in combination with defibrated pulp as a main material, and it is preferable to heat-treat a mixture of a thermoplastic resin, cellulose fibers and a high-molecular water-absorbing polymer.
The high-molecular water-absorbing polymer is the upper layer, the middle layer,
It may be present in any of the lower layers, or may be a mixture with pulp. Further, the high molecular weight water-absorbing polymer is preferably in the form of particles having a retaining property capable of absorbing and retaining a liquid 20 times or more its own weight and having a gelling property. Preferred examples include starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, crosslinked sodium carboxymethyl cellulose, and acrylic acid (salt) polymers.

The moisture permeable film forming the back sheet 2 is a non-porous moisture permeable film made of a specific block copolymerized polyester resin.
The moisture permeable film preferably has a thickness of 5 to 10
0 μm, moisture permeability is preferably 0.5 g / 100 cm
² · Hr or more, more preferably 1.0 to 2.5 g / 10
It is 0 cm ² · Hr, and the water pressure resistance is preferably 2 m or more. If the film thickness is out of the above range, the elasticity is reduced, so it is preferable to set the film thickness in the above range. The stretchability of the moisture-permeable film is preferably such that the permanent strain when stretched by 100% and the stress is released is 40% or less. Here, the above permanent set (%) is obtained by the following formula. Permanent strain (%) = [(length when 100% elongation and stress is released-initial length) / initial length] x 100 If the above permanent set exceeds 40%, the fit of the diaper deteriorates. Is not preferred.

The specific block copolymerized polyester resin forming the moisture permeable film is a block copolymer of a hard component and a soft component.

Preferred examples of the hard component include polyesters obtained by reacting a dicarboxylic acid component and a diol component. Examples of the dicarboxylic acid component include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and naphthalene dicarboxylic acid; aliphatic dicarboxylic acids such as succinic acid, adipic acid, and sebacic acid. , Ethylene glycol, propylene glycol, butanediol, hexamethylene glycol, neopentyl glycol, and other aliphatic diols; cyclohexanedimethanol, paraxylylene glycol, aromatic diols such as bisphenol A adduct of ethylenedioxide with 2 moles, and the like. In each case, they can be used alone or as a mixture.

The dicarboxylic acid component and the diol component are preferably combined by using those having an aromatic ring in at least one of them, and the repeating unit has an average molecular weight linked to the aromatic ring. It is preferable to select and combine the above dicarboxylic acid component and the above diol component so that the amount per ester group is 180 or less, preferably 160 or less.

As the soft component, polyether and / or aliphatic polyester is used. Polyethylene glycol, poly (ethylene / propylene) block polyglycol, polytetramethylene glycol, polyhexamethylene glycol, etc. are used as the polyether, and polyethylene adipate, polybutylene adipate, polycaprolactone, etc. are used as the aliphatic polyester. Is mentioned.

In the block copolymerized polyester resin, the hard component is a polyester of an aromatic dicarboxylic acid and an aliphatic diol or a polyester of an aliphatic dicarboxylic acid and an aromatic diol, and the soft component is a polyester. Ether and / or aliphatic polyesters are preferred. Specifically, the hard component is terephthalic acid, phthalic acid and / or naphthalenedicarboxylic acid,
Desirably, it is a polyester of phthalic acid and / or naphthalenedicarboxylic acid and one or more selected from the group consisting of ethylene glycol, propylene glycol and butanediol, preferably ethylene glycol, propylene glycol and tetramethylene glycol. The soft component is poly (ethylene /
Propylene) block polyglycol and / or polytetramethylene glycol are preferred.

The glass transition temperature (Tg) of the hard component is preferably 50 ° C. or higher, and the glass transition temperature (Tg) of the soft component is preferably 20 ° C. or lower. It is preferable in terms of non-blocking property, moisture permeability, and moldability. Tg of the above hard component is 50
When the temperature is lower than 0 ° C, when used as a backing material of an absorbent article, the shape retention property is poor at the use / storage temperature, and when the Tg of the soft component is higher than 20 ° C, the moisture permeability at the use temperature decreases. Therefore, the above range is preferable.
Here, the glass transition temperature (Tg) is a value obtained by measuring with DSC.

The molecular weight of the block copolymerized polyester resin and the composition ratio of the hard component and the soft component are determined by the types and molecular weights of the dicarboxylic acid component and the diol component used as the hard component, and the polyether used as the soft component. And / or the type and molecular weight of the polyester, and the melt flow index (MF) of the block copolymerized polyester resin as a whole, although it varies depending on the repeating number of the hard component and the soft component.
I) is preferably 1 to 25, more preferably 5 to 1
8. Equilibrium moisture content is preferably 0.30 to 1.40%,
It is more preferable to adjust the molecular weight and the composition ratio so as to be 0.50 to 0.90% from the viewpoints of film strength, non-blocking property, moisture permeability and molding processability.

If the MFI is less than 1, melt molding, etc.
Molding processability is inferior, and if it exceeds 25, tackiness at room temperature
There is strong blocking and poor film shape retention.
Therefore, it is preferably within the above range. Also, the above equilibrium water
If the fraction is less than 0.30%, the water vapor permeability will be low,
If it exceeds 1.40%, the elastic modulus decreases and the shape retention becomes poor.
Since it is inferior and has strong adhesiveness and blocking occurs,
It is preferably within the range. Here, the MFI is A
At 200 ° C. measured according to STMD1238
It is a value. Further, the above block copolymer polyester resin
For fats with a melting point above 180 ° C
MFI is 2 measured according to ASTM D1238.
It is a value at 30 ° C., and the value is in the above range.
preferable. The above equilibrium moisture content is 23 ° C / 0% RH.
W for 48 hours ₀, 23 ° C / 65% R
Weight when stored in H for 48 hours is W₁Then, [(W
₁-W₀) × 100] / W₀Is the value indicated by.

In order to prepare the block copolymerized polyester resin, the hard component and the soft component can be easily obtained by a generally known transesterification reaction. Specifically, as the hard component, It can be manufactured by preparing an oligopolyester composed of terephthalic acid and butanediol in advance, mixing it with polytetramethylene glycol, and performing a melt reaction.

The above-mentioned block copolymerized polyester resin used in the present invention is not only itself but also the decomposition product of the block copolymerized polyester resin is a safe one which does not cause skin irritation and is colored with time. It is a resin that does not exist at all and hardly deteriorates, and is an excellent material as a material for hygiene products such as absorbent articles.

The moisture permeable film can be easily formed from the block copolymerized polyester resin by a known method.

In the underpants type disposable diaper 1 of the present embodiment configured as described above, the back sheet 2 is
A non-woven fabric 6 which is a non-porous moisture permeable film and is intermittently joined to the non-porous moisture permeable film is formed to be stretchable in the width direction of the absorbent body 4, and the back sheet 2 and the non-woven fabric are formed. Since it expands and contracts integrally with 6, the surface sheet 3 can fully utilize the advantages such as touch, liquid permeability and liquid return property, and has the non-porous moisture permeable film used as the back sheet 2. The advantages such as fit can be fully utilized.

<Embodiment 2 (Embodiment of Second Invention)> FIG. 5 is a view corresponding to FIG. 3 showing an embodiment of the present invention (second invention). Absorbent article of this embodiment (pants-type disposable diaper)
1 is a liquid-impermeable backsheet 2, a liquid-permeable topsheet 3, and a space between the backsheet 2 and the topsheet 3, as in the embodiment of the first invention shown in FIG. It has a vertically long absorber 4 and is formed into a pants-like shape.

In the pants-type disposable diaper 1 of this embodiment, as shown in FIG. 5, the back sheet 2 is a moisture-permeable film having stretchable elastic properties, and the top sheet 3 is extensible. A non-woven fabric 6 having a fold of
The back sheet 2 and the top sheet 3 are extended in the width direction of the absorbent body 4 to form extended portions 5, and the extended portions 5 are joined intermittently.

To further explain the present embodiment in detail, the nonwoven fabric 6 has a ridge 6'extending in the longitudinal direction of the absorbent body 4 as shown in FIG. And the recessed section 6 "are alternately arranged,
A fold is formed by the ridge 6'and the ridge 6 ", and the fold is extendable in the width direction of the absorbent body 4. The nonwoven fabric 6 is the back sheet. 2 and the absorber 4 is interposed therebetween, and is intermittently joined to the back sheet 2 via a hot melt adhesive 7 at the outer surface top end of the recessed portion 6 ″ of the extended portion 5. There is. Therefore, the backsheet 2 can be expanded and contracted integrally with the nonwoven fabric 6 in the width direction of the absorber 4. Spacing of the folds in the non-woven fabric 6, that is, the ridges 6 ', 6'
The interval M between them is 0.5 to 1.5 mm. Further, the absorber 4 has upper and side surfaces (the absorber 4).
On both sides parallel to the longitudinal direction of the non-woven fabric 6 and the outer surface apex of the recessed portion 6 ″ of the non-woven fabric 6 is intermittently joined via an adhesive agent 7. Also on the lower surface side, the back sheet 2 and the adhesive agent 7 are joined. It is joined intermittently through.

In the underpants type disposable diaper 1 of the present embodiment configured as described above, the back sheet 2 is
The nonwoven fabric 6 which is a stretchable moisture permeable film and is intermittently bonded to the moisture permeable film is formed so as to be stretchable in the width direction of the absorbent body 4, and the back sheet 2
Since the non-woven fabric 6 and the non-woven fabric 6 expand and contract integrally, the non-woven fabric 6 can fully utilize the advantages of the non-woven fabric 6 such as texture, liquid permeability, and liquid return property, and has the moisture-permeable film used as the back sheet 2. The advantages such as fit can be fully utilized.

<Other Embodiments> FIG. 4 is a sectional view showing a part of another embodiment of the present invention (first invention) with a part thereof omitted. In the pants-type disposable diaper of this embodiment, a surface sheet is used. The configuration is the same as that of the above-described first embodiment, except that the mode of surrounding the absorber is different from that of the above-described first embodiment (the first invention). That is, the pants-type disposable diaper 1 of the embodiment shown in FIG.
Is surrounded by both sides of the bottom surface of the absorber 4,
On the upper surface side of the absorber 4, the hot melt adhesive 7
Is joined to the surface sheet 3 by. Then, the surface sheet 3 is partially folded back to the opposite side of the absorbent body 4 on both sides of the bottom surface of the absorbent body 4, and in the folded back part, a non-woven fabric is formed by the hot melt adhesive 7 (Fig. It is joined to the top end of the ridge (not shown) so as not to hinder the elongation of the nonwoven fabric. Also,
The nonwoven fabric 6 in Examples 1 and 2 can be stretched only in the width direction of the absorbent body 4, but the nonwoven fabric 6 can be stretched only in the longitudinal direction of the absorbent body 4 or in the width direction and the longitudinal direction of the absorbent body 4. It may be possible.

In the second embodiment (embodiment of the second invention) and other embodiments, the explanations in the first embodiment (embodiment of the first invention) are applied to points not particularly described. It

Next, the present invention will be described in more detail by showing production examples of the absorbent article of the present invention (first invention and second invention), but the absorbent article of the present invention is limited to these production examples. It is not something that will be done. <Manufacturing Example 1> This Manufacturing Example 1 is a manufacturing example of the pants-type disposable diaper of the first embodiment. The nonwoven fabric 6 having a large number of stretchable folds in Example 1 has a larger area than the area of the back sheet 2 in a state where no tension is applied to the back sheet 2 (so-called free tension state) [fold processing. Non-woven fabric before applying (hereinafter, Non-woven fabric N
In this case, it means a non-woven fabric before fold processing. )] Is used. In particular,
A method of pre-folding (crepe) the non-woven fabric N by a method such as Mic Rex processing, and the non-woven fabric N and the back sheet 2 stretched in one direction so as to have the same area as the non-woven fabric N are intermittently formed. Examples include a method in which the non-woven fabric N is pleated by joining.

As a method of joining the non-woven fabric 6 having the folds formed by the above method and the back sheet 2 to each other, there is a method of using an adhesive such as a hot melt adhesive. An adhesive is applied to the outer surface apex of the crease 6 ″ of the folds. Further, the non-woven fabric 6 formed by the above method and the back sheet 2 are joined together without using the adhesive. Alternatively, a thermoplastic elastomer may be used as the material, and the thermoplastic elastomer 2 may be brought into contact with the top end of the outer surface of the concave streak portion 6 ″ of the fold portion of the nonwoven fabric 6, and then the both may be subjected to composite processing.

As a method for joining the nonwoven fabric N and the back sheet 2 when forming the fold-containing nonwoven fabric 6 by the above method, a joining method using an adhesive such as a hot melt adhesive, heat sealing or A joining method using ultrasonic embossing or the like may be used. In the above method, when the hot melt adhesive is used, the hot melt adhesive is pattern-coated in a dot shape or a linear shape on the back sheet (moisture permeable film) 2 or the nonwoven fabric N. Among these patterns, the dot pattern is particularly preferable. In this case, the application of the adhesive may be performed before or after stretching the back sheet (moisture permeable film). Also,
In the above method, when a method such as heat sealing or ultrasonic embossing is used, the back sheet 2 and the non-woven fabric N are joined intermittently by forming the roll pattern into a dot-shaped or linear-shaped pattern. can do.

In the case of the above method, the stretching direction of the back sheet (moisture permeable film) 2 may be only in the width direction of the absorber 4, only in the longitudinal direction of the absorber 4, or in both directions. However, when the above linear pattern is used as the pattern of the adhesive or the like, the extension direction of the back sheet 2 is the width direction of the absorbent body 4, and in this case, the linear direction of the linear pattern. And the stretching direction of the back sheet are orthogonal to each other.

In the above method, when bonding is performed using a dot-shaped or linear-shaped adhesive pattern, the size and interval of the adhesive patterns should be determined according to the construction of the pants-type disposable diaper and the expansion and contraction required for the absorbent article described later. It is preferable to appropriately select in consideration of the rate, and when joining using a linear pattern, it is preferable to apply intermittently. Furthermore, when a nonwoven fabric having elastic elasticity is used as the nonwoven fabric 6, pattern bonding can be performed by a hot melt adhesive, heat sealing, ultrasonic embossing or the like. When the pattern is dot-shaped, the dot-shaped area is 0.05 ~
3.0 mm ^2, preferably 0.6 to 1.0 mm ^2, the interval distance between each dot 3.0～7.0Mm, preferably 3.0 to 5.0 mm. When the pattern has a linear shape, its width is preferably 0.5 to 1.5 mm.
Is. It should be noted that these numerical values are the numerical values in the bonded sheet after the non-woven fabric N and the back sheet (moisture permeable film) 2 are bonded together and then the back sheet returns to the unstretched state.

When the back sheet 2 and the nonwoven fabric 6 are joined by the above method, the area ratio between the back sheet 2 (the moisture permeable film having elastic properties) and the nonwoven fabric N in the free tension state (free). Is the area of the backsheet 2 in tension: the area of the non-woven fabric) the same as the required expansion / contraction rate of the backsheet 2 when tension is applied to the backsheet 2 in the width direction or the longitudinal direction of the absorber 4. It is preferably larger than that. The area ratio is preferably 1 to 1.1: 5.0,
The ratio is more preferably 1 to 1.2: 3, and is preferably set as appropriate according to the method of joining the back sheet 2 and the nonwoven fabric or the designing method.

In the pants-type disposable diaper 1, the area ratio is set to be small in a portion where a high expansion / contraction rate is not required, and in a portion where a high expansion / contraction rate is required,
Although it is preferable to set the area ratio to a large value, the expansion / contraction rate required for the absorbent article is 1.1 to 5 in the width direction or the longitudinal direction of the absorbent body 4 at the portion to which the elasticity is to be imparted. It is preferably set to be 0.0 times. If the expansion / contraction ratio is less than 1.1 times, the pants-type disposable diaper 1 becomes difficult to apply, and if it exceeds 5.0 times, the ratio of the folds of the nonwoven fabric 6 when the back sheet 2 is in the free tension state. Is increased, which may adversely affect the absorbability and diffusibility of excrement, which is not preferable.

Thus, in this Production Example 1, the hot-melt adhesive is stretched in the width direction of the absorber 4 on the back sheet 2 or the nonwoven fabric N, and the absorber 4 in FIG.
Is applied linearly (linearly) in the width direction of the absorbent body 4 at regular intervals in the longitudinal direction. Then, these are joined and the stretched state of the back sheet (moisture permeable film) is released to form folds in the nonwoven fabric N in the width direction of the absorbent body 4 (the ridges of the folds). The portion and the concave streak portion are formed along the longitudinal direction of the absorber 4). Then, the absorbent body 4 surrounded by the topsheet 3 in advance is placed on the non-woven fabric 6 joined to the backsheet in this manner, and the topsheet 3 and the nonwoven fabric 6 are combined at the top end of the ridge 6 '. Join intermittently at. After that, a pant-type diaper is formed by a conventional method.

<Manufacturing Example 2> This Manufacturing Example 2 is a manufacturing example of the pants-type disposable diaper of the second embodiment. The non-woven fabric 6 having a large number of stretchable folds in Example 2 is formed by the method described in Production Example 1. Thus, in this Production Example 2, the hot melt adhesive 7 is linearly coated on the outer surface apexes of the creases 6 ″ of the folds of the non-woven fabric 6. However, in the non-woven fabric 6 described above, At the site where the absorber 4 is covered, the hot melt adhesive 7 is linearly applied to a part of the groove 6 ″, as shown in FIG. Next, the non-woven fabric coated with the adhesive (top sheet 3) 6 is placed on the back sheet 2 on which the absorber 4 has been placed at a predetermined position in advance, and both are intermittently joined at the extending portion 5. At the same time, the nonwoven fabric 6 and the absorber 4 are also joined intermittently. After that, a pant-type diaper is formed by a conventional method.
Also in the second manufacturing example, the description of the first manufacturing example is applied to the portions not particularly described in detail.

The present invention is not limited to the above examples and the above production examples. For example, as the non-woven fabric 6 in Example 1, the one produced by the above method can be used. Nonwoven fabric 6 in Example 2
The above-mentioned method can also be applied to the formation of. Needless to say, other changes can be made without departing from the spirit of the present invention. The absorbent article of the present invention is preferably a pants-type disposable diaper as shown in FIG. 1, but is an open-type diaper or a flat-type disposable diaper (including incontinence) and a so-called training pants. Is also good.

[0059]

EFFECT OF THE INVENTION The absorbent article of the present invention takes full advantage of the advantage of the non-woven fabric which is usually used in disposable diapers and the advantage of using the film having the moisture permeability and the stretch elastic property as the back sheet. It is a thing. More specifically, the absorbent article of the present invention is stretchable by using a moisture-permeable stretchable film for the back sheet, so that when it is worn by the user, it stretches in the girth direction to the body. Since the back sheet has a good fit property and the back sheet has moisture permeability, the problem of stuffiness does not occur.

[Brief description of drawings]

FIG. 1 is a perspective view showing a pants-type disposable diaper showing an embodiment of the present invention (first invention).

2 is a development view of the pants-type disposable diaper shown in FIG. 1. FIG.

3 is a cross-sectional view taken along line I-I in FIG.

FIG. 4 is a sectional view showing a part of another embodiment of the present invention (first invention).

FIG. 5 is a view corresponding to FIG. 3 showing an embodiment of the present invention (second invention).

[Explanation of symbols]

 1 Absorbent Article 2 Back Sheet 3 Top Sheet 4 Absorber 5 Extended Section 6 Nonwoven Fabric 7 Hot Melt Adhesive

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location A61F 5/44 H 7108-4C B32B 5/02 C 9349-4F 27/00 K 9349-4F 27 / 12 9349-4F

Claims (10)

[Claims] 1. An absorbent article comprising a liquid-impermeable backsheet, a liquid-permeable topsheet, and a vertically long absorber disposed between the backsheet and the topsheet, wherein: The back sheet is a non-porous moisture-permeable film formed of a block-copolymerized polyester resin of a hard component and a soft component, and the stretchable nonwoven fabric is bonded onto the moisture-permeable film. Sex goods. 2. The block copolymerized polyester resin has a melt flow index of 1 to 25 and an equilibrium moisture content of 0.30% to 1.40%, and
The glass transition temperature (Tg) of the hard component is 50 ° C. or higher, and the glass transition temperature (Tg) of the soft component is 20.
The absorbent article according to claim 1, which has a temperature of not higher than ° C. 3. The hard component is a polyester of an aromatic dicarboxylic acid and an aliphatic diol or a polyester of an aliphatic dicarboxylic acid and an aromatic diol, and the soft component is a polyether and / or an aliphatic polyester. The absorbent article according to claim 1 or 2, wherein the absorbent article is present. 4. The hard component is a polyester of phthalic acid and / or naphthalenedicarboxylic acid and one or more selected from the group consisting of ethylene glycol, propylene glycol and butanediol, and the soft component is a polyester. The absorbent article according to claim 3, which is (ethylene / propylene) block polyglycol and / or polytetramethylene glycol. 5. The moisture-permeable film has a thickness of 5 to 5.
100μm, moisture permeability 0.5g / 100cm ² · H
It is r or more, the water pressure resistance is 2 m or more, and the basis weight of the non-woven fabric and paper is 10 to 100 g / m ² , and the absorbability according to any one of claims 1 to 4. Goods. 6. The non-woven fabric has a large number of stretchable pleats, and is intermittently joined to the non-porous moisture-permeable film, according to any one of claims 1 to 5. The absorbent article according to item 1. 7. The absorbent article according to claim 1, wherein the nonwoven fabric is stretchable in a width direction and / or a longitudinal direction of the absorbent body. 8. The surface sheet, wherein the absorbent body is surrounded by the surface sheet to at least both sides of the bottom surface of the absorbent body and is intermittently coupled to the surface sheet, and is located on the bottom surface of the absorbent body. The non-woven fabric is intermittently joined to the non-woven fabric according to any one of claims 1 to 7. 9. An absorbent article comprising a liquid-impermeable backsheet, a liquid-permeable topsheet, and a vertically elongated absorber disposed between the backsheet and the topsheet, wherein: The back sheet is a non-porous moisture permeable film formed of a block-copolymerized polyester resin of a hard component and a soft component, and the top sheet is a nonwoven fabric having a large number of stretchable folds, The absorbent article, wherein the sheet and the topsheet are extended in the width direction of the absorber to form an extended portion, and are joined intermittently at the extended portion. 10. The absorbent article according to claim 9, wherein the nonwoven fabric is extensible in a width direction and / or a longitudinal direction of the absorbent body.